Hot-blast road repairing machine



Dec. s., 195o W. G. CHAUSSE HOT-BLAST ROAD REPAIRING MACHINE Filed July 12, 1946 I IVIIIL W@ AMI... f

Patented Dec. 5, 1950 UNITED STATES PATENT GFFICE This invention relates to road repairing machinery and, in particular, to machinery for repairing cracks in roadways.

One object of this invention is to provide a portable machine for cleaning out cracks in roadways and preparing them for iilling.

Another object is to provide a portable machine for cleaning out cracks in roadways by means of a blast of extremely hot air which not only burns out combustible material in the cracks but also blows out the products of combustion and also non-combustible material such as dirt.

Another object is to provide a portable machine for cleaning out cracks in roadways as set forth in the preceding objects, wherein the machine is provided with a self-contained burner which heats compressed air as the latter pursues a labyrinthine path on its way to a nozzle through which it is expelled into the cracks.

Another object is tovprovide a portable machine for cleaning out cracks in roadways as set forth in the preceding objects, wherein the burner and the nest of pipes constituting the labyrinthine path for the compressed air are housed in a small, compact chamber mounted on wheels and preferably having handles for convenient manipulation of the nozzle relatively to the cracks.

Another object is to provide a portable machine for cleaning out cracks in roadways having means for heating a compressed air blast which emerges from a nozzle hot enough to burn and blow foreign matter out of the cracks but not containing flame and not hot' enough to chip or otherwise damage the side walls of the cracks.

Other objects and advantages of the invention will become apparent during the course of the following description of the accompanying drawings, wherein:

Figure l is a top plan view of an improved machine for cleaning out cracks in roadways, partly broken away to disclose the interior, according to a preferred embodiment oi the invention;

Figure 2 is a side elevation of the machine shown in Figure l, likewise partly broken away to disclose the internal construction;

Figure 3 is a vertical cross-section along the line 3-3 in Figure 2; and

Figure 4 is a vertical cross-section along the line 4-4 in Figure 2.

Referring to the drawing in detail, Figures 1 and 2 show a preferred embodiment of the roadway crack-cleaning machine of this invention as consisting of a hollow oven l having insulating walls composed of refractory material, these walls consisting of a top Wall Il, bottom wall l2, front wall i3 and rear wall I4, and right and left side walls l5 and I6 respectively, these being enclosed by a housing l1 of metal plate or other suitable material.

Bolted as at I8 to the underside of the oven I0 approximately beneath the center of gravity of the machine, as is apparent from Figure 2, are spaced journal brackets I9 having an axle 20 journaled therein. Mounted on the axle and secured thereto are wheels 2| by which the machine is moved from place to place. Bolted as at 22 to the opposite sides of the housing I1 are upwardly angled arms 23 terminating in handles 24 arranged for convenient grasp by the operator. Likewise bolted as at 25 to the housing l1 are angle brackets 26 having arcuate portions 21 upon which is mounted a liquid fuel tank 28 having a filling spout 29. Connected to the bottom of the liquid fuel tank 28 is a pipe 30 leading downwardly to a valve 3l controlled by a hand wheel 32. From the valve 3| a conduit 33 leads into a heater, such as an oil burner, generally designated 34, having a casing which passes inwardly through an opening 36 into the interior chamber 31 of the oven I0. The oil burner 34 terminates in a conical flame guard 38. The oil burner 34 is of a convenient type and its details form no part of the present invention, many such oil burners being suitable for the purpose. Fastened to one of the arms 23 near the handle 24 thereof is a bracket 39 carrying a compressed air valve 40 having a valve plunger 4l. The latter carries a collar 42 by which it is urged upwardly by means of a coil spring 43. Extending upwardly from the valve 40 is an arm 44 carrying a pivot pin 45 upon which the valve lever 46 is pivotally mounted. Connected as at 41 is a compressed air supply pipe 48, the opposite end of which is connected to a suitable source of compressed air (not shown), such as an air compresser. Such portable air compressors are well known and their details form no part of the invention.

Extending downwardly from the opposite side of the valve 40 from the connection 41 with the valve plunger 4I and valve seat (not shown) therebetween is a compressed air conduit 49 which passes through the opening 50 in the rear wall i4 to the interior chamber 31 of the oven I0, where it is connected to the heating duct, generally designated 5I mounted upon a supporting plate with downwardly bent opposite ends which rest upon the bottom wall I2 of the oven I0. Connected to the opposite end of the heating duct 5| is an outlet pipe 52 which passes outwardly through an opening 53 in the front wall |3 of the oven I0 to a swivel joint 54 from which a nozzle pipe passes downwardly to a nozzle 55.

The swivel connection 54 permits the nozzle pipe 55 to be adjusted to different angles relatively to the ground level 51 (Figure 2) in order to adjust the position of the nozzle 56 relatively to the cracks which it is intended to clean out. In order to provide such adjustment, a clamp 58 encircles the nozzle pipe 55 and is provided with a bolt 59 operating in a slot 60 in an arm 6| (Figure 2) pivoted as at 62 to the angle bracket 63, the latter being secured to the front wall of the housing il. The bolt 59 is held in its adjusted position within the slot 60 by a wing nut 64.

The heating duct 5| (Figures 2, 3 and 4) consists of a plurality of large diameter external pipes E5 having internal pipes 66 extending therethrough, these being interconnected at their ends by the annular closures Gl. This construction thereby provides an open-ended central passageway 58 in each pipe for the flame and heat from the oil burner 35 to pass through, and an annular chamber 69 between the pipes 65 and 6B. The pipes 65 are interconnected by short pipes 10 arranged alternately at opposite ends thereof so that the annular chambers 69 are connected'in series, such that the compressed air entering the heating duct 5! passes through the entire length of the rst pipe to the front end of its annular chamber 69, whence it passes upwardly through the first cross pipe l0 to the front end of the next pipe 65. The air then passes to the rear end of the second annular chamber G9 -there it ascends through the second cross pipe 'lo into the third pipe 65 and so forth, by zigzag path, emerging through the outlet pipe 52, swivel joint 54, nozzle pipe 55 and nozzle 55.

In the operation of the invention, assuming the fuel tank to be lled with fuel and compressed air supplied through the compressed air line 4S from a suitable air compressor (not shown), the valve 3| is opened by turning the hand wheel so as to provide fuel for the oil burner 35. The latter is ignited and projects intense heat and flame thrbugh the passageways 68 in the heating duct 5|, the hot gases then passing rearwardly through the upper portion of the chamber El' and outward to the atmosphere through the ue 1|. Meanwhile, the operator ias steered` the machine by means of the handles 24 until the nozzle 55 is over the crack to be @leaned out, the position of the axle 20 approximately beneath the center of gravity of the machine enhancing the maneuverability thereof by means of the handles 24, thereby enabling the operator to steer the machine easily and to enable it to follow a winding roadway crack with facility. He then shifts the operating lever 46 of the compressed air valve 40, causing a blast of compressed air to pass through the pipe 49 into the heating duct 5| which has by now been heated to a high temperature by the oil burner 35.

As the blast of compressed air pursues its labyrinthine or zigzag path through the heating duct 5|, it emerges into the outlet pipe 52Y in an intensely heated condition and passes through the widening the crack.

swivel joint 54 and nozzle pipe 55 through the nozzle 56 downwardly into the crack. The force of the blast blows out of the crack any dust or similar foreign matter which is lodged therein while the high temperature of the blast burns out any combustible material. The blast is s0 hot that if it encounters a root in the crack, it kills the root so that the plant or weed does not grow again. The charred substances which are the products of combustible material in the crack, are blown out by the blast and thus do not protect underlying layers of material which it is desired to remove.

The temperature of the blast, while intensely hot, contains no flame and is not hot enough to cause the walls of the crack to chip or fracture, but leaves them clean and substantially free from foreign matter. The bituminous material for repairing the crack can thus be easily inserted therein and penetrates to a great depth, thereby giving it permanence and freedom from dislodgement under the influence of weather. As the blast cleans out each portion of the crack, the machine is pushed forward bythe operator and at the same time steered by the handles 24, sro that the nozzle 5E remains close to the crack and follows its course closely.

Hitherto, roadway cracks have been cleaned out either by digging them out mechanically or by burning them out with a flame. Mechanically digging these cracks out is a. slow and laborious operation performed only at high cost and causing injury to the side walls of the cracks, chipping or fracturing the adjacent pavement and On the other hand, when a flame has been employed, it merely burns out the overlying layer of combustible material, the charred substances resulting therefrom remaining the crack and protecting the underlying foreign matter in the crack. The llame also heats the side walls of the crack to too high a temperature, causing them to fracture and injuring the pavement. The flame, while hot, lacks sulilcient force to expel the charred substances or the dirt which is non-combustible. If the crack is not cleaned out to a suilicient depth, a poor junction is obtained between the filling material and the crack and the nlling material soon becomes dislodged under conditions of weather and traffic, and prior methods fail in this respect.

The present invention, however, by the use of an intensely hot compressed air blast not only burns out the combustible material, but blows out the charred substances remaining as well as the non-combustible dirt and other foreign substances mixed with it, and hence cleans out the crack to a suicient depth to insure a good junction with the ller material. It also kills any vegetation growing in the crack and prevents its future growth, such vegetation often becoming thick and tenacious in cracks in side roads which have remained unrepaired for long periods of time.

While I have shown and described my invention in detail, it is to be understood that the same is to be limited only by the appended claims. for many changes may be made without departing from the spirit and scope of my invention.

What I claim is:

l. A roadway crack-cleaning machine comprisr ing a movable support having an oven thereon, a compressed air heating duct mounted in said oven, a compressed air supply conduit connected to said heating duct, a compressed air outlet conduit connected to said heating duct remote from said supply conduit, a nozzle connected to said outlet conduit forwardly of said support and adapted to be directed downwardly into close proximity to the roadway, a heater mounted adjacent said heating duct, a handle structure connected to said support for guiding said nozzle alo-ng the cracks in the roadway, a transverselydisposed axle structure mounted on said support approximately beneath the center of gravity of said machine, and a pair of ground-engaging supporting wheels mounted on said axis structure whereby to sustain the major portion of the weight of said machine on said pair of wheels and facilitate the maneuverability of said machine.

2. A roadway crack-cleaning machine comprising a movable support having an oven thereon, a compressed air heating duct mounted in said oven, a compressed air supply conduit connected to said heating duct, a compressed air o-utlet conduit connected to said heating duct remote from said supply conduit, a nozzle connected to said outlet conduit forwardly of said support and adapted to be directed downwardly into close proximity to the roadway, a heater mounted adjacent said heating duct, a handle structure connected to said support for guiding said nozzle along the cracks in the roadway, said handle structure being connected to the rearward end of said support and said nozzle being mounted adjacent the forward end of said support, a transversely-disposed axle structure mounted on said support approximately beneath the center of gravity of said machine, and a pair it of ground-engaging supporting wheels mounted on said axis structure whereby to sustain the major portion of the weight of said machine on said pair of wheels and facilitate the maneuverability of said machine.

3. A roadway crack-cleaning machine comprising a movable support having an oven thereon, a compressed air heating duct mounted in said oven, a compressed air supply conduit connected to said heating duct, a compressed air outlet conduit connected to said heating duct remote from said supply conduit, a nozzle connected to said outlet conduit forwardly of said support and adapted to be directed downwardly into close proximity to the roadway, a heater mounted adjacent said heating duct, a handle structure connected to said support for guiding said nozzle along the cracks in the roadway, a compressed air control valve mounted adjacent said Vhandle structure, a transversely-disposed axle structure mounted on said support approximately beneath the center of gravity of said machine, and a pair of ground-engaging supporting wheels mounted on said axis structure whereby to sustain the major portion of the weight of said machine on said pair of wheels and facilitate the maneuverability of said machine.

WILFRED G. CHAUSSE'.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 618,266 Gilman Jan. 24, 1899 707,111 Hopkins Aug. 19, 1902 864,062 Ballintine Aug. 20, 1907 1,031,104 Bellew July 2, 1912 1,072,728 I-Ioldsworth Sept. 9, 1913 1,719,080 Posey July 2, 1929 1,760,459 Weed May 27, 1930 1,946,262 Adams Feb. 6, 1934 2,410,353 McCollum Oct. 29, 1946 FOREIGN PATENTS Number Country Date 836.105 France Oct. 10, 1938 

